The project“Como in the XVIII century” is a project born within the course of Geographic Information Systems (GIS) in the Master of Science in IAT (Environmental and Geomatic Engineering) of Politenico di Milano (Como Campus), Academic Year 2008-2009. The aim of the project is the realization of a webGIS that can collect all the available information about the city of Como in the XVIII century. This work originates from the finding of an ancient city-map of 1722, given to University from Comune di Como and then rectified and geo-referenced in UTM coordinates using the PCI OrthoEngine software. The city has been divided in 11 areas of almost homogeneous extent, each of them assigned to a different group of students (made by two or three people).The webGIS has been realized through UMN MapServer, an open-source development environment for the webGIS implementation created by the University of Minnesota in 1993. Two main elements have to be defined to realize such a kind of GIS: the mapfile and the template file. The first is a text file with specific extension .map, and defines map configuration and visualization properties such as layers, their cartographic projection, the colours, the symbols, etc. The second is instead a simple HTML page that represent the user-webGIS interface. A first way to realize it is to use the MapServer CGI (Common Gateway Interface) program, which constructs the webGIS visualization through references, placed in the template and referred to specific parameters. The second way, the one used in the project, considers instead the use of Chameleon, a PHP application that enables to obtain more advanced and interactive functionalities (like zoom box, query box, etc.) by means of basic premade components called widgets.

The Area 5Area 5, as we can see from the figure, is located almost in the centre of Como walled city. It’s delimited from the actual Lambertenghi and Collegio dei Dottori streets on the North, Luini and Odelaschi streets and S.Fedele square on the East, Giovio street on the South and Diaz street on the West.In the XVIII century, this area of Como contained some important religious buildings whose remains are today very few: S.Giovanni in Atrio Baptistery, placed in front of S.Fedele basilica, and two of the three ancient city monasteries, S.Eufemia and S.Anna. On the opposite, Nattas’ Palace is still well-conserved today thanks to a recent restoration: it was the old residence of Nattas’ family (to whom the neighbouring street is also dedicated) and the actual seat of the Protectorate of Insubria University and of a Center of Politecnico di Milano. Some buildings located near S.Fedele square (in the past called Mercato del Grano square and center of urban bisiness) can still today show their particularity, as their wooden structures are easily visible yet.

Our webGISEntering the webGIS, it’s possible to visualize the XVIII city map, whose Area 5-buildings have been digitalized; the map allows also to visualize the streets, obtained again by a digitalization of the original map. A set of tools to comprehend and query the present elements is available on the map sides.

On the left, from the top to the bottom, is located the English-language legend, in which residential buildings are blue-coloured, monasteries are red-coloured and worships are green-coloured; in the following there is a series of buttons for updating the map, zooming in and out, measuring distances and requesting information about streets and buildings (query); then there is the value of the zoom factor, a textfield that shows the result of ruler measured distances and the cursor position on the map in UTM coordinates. On the right, always from the top to the bottom, there are the global reference map, to whom we can every time refer the visualized portion, the map scale and the map extension, which is defined by the minimum and maximum X and Y coordinates. Finally, in the bottom of the webGIS there is the scalebar, that allows to visually evaluate distances on the map.Using the query bottom we can obtain some information about buildings and streets, contained in a table. Particularly for the buildings, clicking on the GROUP_DESC link it’s possible to access web pages (in English and Italian) in which there are a brief description of the block, its parcel division evolution (reconstructed from different cadastral maps) and links to other web pages (always in English and Italian) with additional material related to relevant buildings. Infact, some other web pages with information and photos (took by us) have been realized for a number of significant buildings and streets; the direct link to these pages is also present in the query results-table in the MORE_INFO row.